Activation of Lactate Receptor Positively Regulates Skeletal Muscle Mass in Mice

G protein-coupled receptor 81 (GPR81), a selective receptor for lactate, expresses in skeletal muscle cells, but the physiological role of GPR81 in skeletal muscle has not been fully elucidated. As it has been reported that the lactate administration induces muscle hypertrophy, the stimulation of GPR81 has been suggested to mediate muscle hypertrophy. To clarify the contribution of GPR81 activation in skeletal muscle hypertrophy, in the present study, we investigated the effect of GPR81 agonist administration on skeletal muscle mass in mice. Male C57BL/6J mice were randomly divided into control group and GPR81 agonist-administered group that received oral administration of the specific GPR81 agonist 3-Chloro-5-hydroxybenzoic acid (CHBA). In both fast-twitch plantaris and slow-twitch soleus muscles of mice, the protein expression of GPR81 was observed. Oral administration of CHBA to mice significantly increased absolute muscle weight and muscle weight relative to body weight in the two muscles. Moreover, both absolute and relative muscle protein content in the two muscles were significantly increased by CHBA administration. CHBA administration also significantly upregulated the phosphorylation level of p42/44 extracellular signal-regulated kinase-1/2 (ERK1/2) and p90 ribosomal S6 kinase (p90RSK). These observations suggest that activation of GRP81 stimulates increased the mass of two types of skeletal muscle in mice in vivo. Lactate receptor GPR81 may positively affect skeletal muscle mass through activation of ERK pathway.

SNIP1 and PRC2 coordinate cell fates of neural progenitors during brain development

Stem cell survival versus death is a developmentally programmed process essential for morphogenesis, sizing, and quality control of genome integrity and cell fates. Cell death is pervasive during development, but its programming is little known. Here, we report that Smad nuclear interacting protein 1 (SNIP1) promotes neural progenitor cell survival and neurogenesis and is, therefore, integral to brain development. The SNIP1-depleted brain exhibits dysplasia with robust induction of caspase 9-dependent apoptosis. Mechanistically, SNIP1 regulates target genes that promote cell survival and neurogenesis, and its activities are influenced by TGFβ and NFκB signaling pathways. Further, SNIP1 facilitates the genomic occupancy of Polycomb complex PRC2 and instructs H3K27me3 turnover at target genes. Depletion of PRC2 is sufficient to reduce apoptosis and brain dysplasia and to partially restore genetic programs in the SNIP1-depleted brain in vivo. These findings suggest a loci-specific regulation of PRC2 and H3K27 marks to toggle cell survival and death in the developing brain.

Investigation of removal and inactivation efficiencies of human sapovirus in drinking water treatment processes by applying an in vitro cell-culture system

Here, we examined the efficiencies of drinking water treatment processes for the removal and inactivation of human sapovirus (HuSaV). We applied a recently developed in vitro cell-culture system to produce purified solutions of HuSaV containing virus concentrations high enough to conduct virus-spiking experiments, to develop an integrated cell culture-polymerase chain reaction (ICC-PCR) assay to quantify the infectivity of HuSaV, and to conduct virus-spiking experiments. In virus-spiking coagulation-sedimentation-rapid sand filtration (CS-RSF) and coagulation-microfiltration (C-MF) experiments, HuSaV removals of 1.6-3.7-log₁₀ and 1.2->4.3-log₁₀, respectively, were observed. The removal ratios observed with CS-RSF were comparable and correlated with those of murine norovirus (MNV, a widely used surrogate for human noroviruses) and pepper mild mottle virus (PMMoV, a potential surrogate for human enteric viruses in physical and physicochemical drinking water treatment processes), and those observed with C-MF were higher than but still correlated with those of MNV and PMMoV, indicating that MNV and PMMoV are both potential surrogates for HuSaV in CS-RSF and C-MF. For astrovirus (AstV, a representative human enteric virus), removal ratios of 1.8-3.3-log₁₀ and 1.1->4.0-log₁₀ were observed with CS-RSF and C-MF, respectively. The removal ratios of AstV observed with CS-RSF were comparable and correlated with those of PMMoV, and those observed with C-MF were higher than but still correlated with those of PMMoV, indicating that PMMoV is a potential surrogate for AstV in CS-RSF and C-MF. When the efficacy of chlorine treatment was examined by using the developed ICC-PCR assay, 3.8-4.0-log₁₀ inactivation of HuSaV was observed at a CT value (free-chlorine concentration [C] multiplied by contact time [T]) of 0.02 mg-Cl₂·min/L. The infectivity reduction ratios of HuSaV were comparable with those of MNV. For AstV, 1.3-1.7-log₁₀ and >3.4-log₁₀ inactivation, as evaluated by ICC-PCR, was observed at CT values of 0.02 and 0.09 mg-Cl₂·min/L, respectively. These results indicate that HuSaV and AstV are both highly sensitive to chlorine treatment and more sensitive than a chlorine-resistant virus, coxsackievirus B5 (1.3-log₁₀ inactivation at a CT value of 0.4 mg-Cl₂·min/L, as evaluated by the ICC-PCR assay).

Phosphorylation of 53BP1 by ATM enforce neurodevelopmental programs in cortical organoids

53BP1 is a well-established DNA damage repair factor recently shown to regulate gene expression and critically influence tumor suppression and neural development. For gene regulation, how 53BP1 is regulated remains unclear. Here, we showed that 53BP1-serine 25 phosphorylation by ATM is required for neural progenitor cell proliferation and neuronal differentiation in cortical organoids. 53BP1-serine 25 phosphorylation dynamics controls 53BP1 target genes for neuronal differentiation and function, cellular response to stress, and apoptosis. Beyond 53BP1, ATM is required for phosphorylation of factors in neuronal differentiation, cytoskeleton, p53 regulation, and ATM, BNDF, and WNT signaling pathways for cortical organoid differentiation. Overall, our data suggest that 53BP1 and ATM control key genetic programs required for human cortical development.

Relationships among Grip Strength Measurement, Response Time, and Frailty Criteria

BACKGROUND

Muscle response in older adults is believed to decrease with maximal muscle strength, although it has not been adequately assessed; further, the relationship between frailty and muscle response remains unexamined.

OBJECTIVES

This study aimed to develop a practical method for measuring muscle response using grip strength in older adults and to clarify the relationship between frailty and grip strength response.

DESIGN, SETTING, AND PARTICIPANTS

We performed a cross-sectional, clinical, observational study. A total of 248 patients (94 men and 154 women, mean age: 78.2 years) who visited the outpatient unit in the Integrated Healthy Aging Clinic of our Hospital for the first time were enrolled.

MEASUREMENTS

Using a grip strength measuring device originally developed by us, we measured grip strength response indices, such as reaction time, time constant, rate of force development (response speed), and maximum grip strength. Grip strength response indices were compared among three groups (robust, pre-frail, and frail) according to the Fried and Kihon checklist assessments for frailty.

RESULTS

Based on Fried's assessment, marked differences were found between groups not only in maximal grip strength but also in response time and response speed. Based on the Kihon checklist assessment, there was no significant difference in response time; however, a considerable difference in response speed for the left hand was observed. Moreover, according to the Kihon checklist assessment, some cases showed differences in muscle response although not in maximal muscle strength.

CONCLUSIONS

The response speed of grip strength was suggested to decrease with frailty. The results suggest that measurement of grip strength response in both hands is useful to examine the relationship between frailty and grip strength response.

CUT & RUN to Profile Chromatin-Bound Proteins in Primary Mouse Neural Progenitor Cells

Cleavage under targets and release using nuclease (CUT & RUN) is an innovative method to profile histone modifications and chromatin-bound proteins genome-wide. CUT & RUN offers two distinct advantages of requiring much fewer cells and providing strong signal-to-noise ratios in deep-sequencing data. Here, we describe a workflow starting from dissociation and sorting of mouse embryonic brains, CUT & RUN, and DNA library preparation to deep sequencing. With our workflow, researchers can obtain high-quality sequencing data to profile histones and chromatin-associated proteins by using as few as 100,000 neural progenitor cells (NPCs).

Evaluation of reduction efficiencies of pepper mild mottle virus and human enteric viruses in full-scale drinking water treatment plants employing coagulation-sedimentation-rapid sand filtration or coagulation-microfiltration

Here, we evaluated the reduction efficiencies of indigenous pepper mild mottle virus (PMMoV, a potential surrogate for human enteric viruses to assess virus removal by coagulation-sedimentation-rapid sand filtration [CS-RSF] and coagulation-microfiltration [C-MF]) and representative human enteric viruses in four full-scale drinking water treatment plants that use CS-RSF (Plants A and B) or C-MF (Plants C and D). First, we developed a virus concentration method by using an electropositive filter and a tangential-flow ultrafiltration membrane to effectively concentrate and recover PMMoV from large volumes of water: the recovery rates of PMMoV were 100% when 100-L samples of PMMoV-spiked dechlorinated tap water were concentrated to 20 mL; even when spiked water volume was 2000 L, recovery rates of >30% were maintained. The concentrations of indigenous PMMoV in raw and treated water samples determined by using this method were always above the quantification limit of the real-time polymerase chain reaction assay. We therefore were able to determine its reduction ratios: 0.9-2.7-log10 in full-scale CS-RSF and 0.7-2.9-log10 in full-scale C-MF. The PMMoV reduction ratios in C-MF at Plant C (1.0 ± 0.3-log10) were lower than those in CS-RSF at Plants A (1.7 ± 0.5-log10) and B (1.4 ± 0.7-log10), despite the higher ability of MF for particle separation in comparison with RSF owing to the small pore size in MF. Lab-scale virus-spiking C-MF experiments that mimicked full-scale C-MF revealed that a low dosage of coagulant (polyaluminum chloride [PACl]) applied in C-MF, which is determined mainly from the viewpoint of preventing membrane fouling, probably led to the low reduction ratios of PMMoV in C-MF. This implies that high virus reduction ratios (>4-log10) achieved in previous lab-scale virus-spiking C-MF studies are not necessarily achieved in full-scale C-MF. The PMMoV reduction ratios in C-MF at Plant D (2.2 ± 0.6-log10) were higher than those at Plant C, despite similar coagulant dosages. In lab-scale C-MF, the PMMoV reduction ratios increased from 1-log10 (with PACl [basicity 1.5], as at Plant C) to 2-4-log10 (with high-basicity PACl [basicity 2.1], as at Plant D), suggesting that the use of high-basicity PACl probably resulted in higher reduction ratios of PMMoV at Plant D than at Plant C. Finally, we compared the reduction ratios of indigenous PMMoV and representative human enteric viruses in full-scale CS-RSF and C-MF. At Plant D, the concentrations of human norovirus genogroup II (HuNoV GII) in raw water were sometimes above the quantification limit; however, whether its reduction ratios in C-MF were higher than those of PMMoV could not be judged since reduction ratios were >1.4-log10 for HuNoV GII and 2.3-2.9-log10 for PMMoV. At Plant B, the concentrations of enteroviruses (EVs) and HuNoV GII in raw water were above the quantification limit on one occasion, and the reduction ratios of EVs (>1.2-log10) and HuNoV GII (>1.5-log10) in CS-RSF were higher than that of PMMoV (0.9-log10). This finding supports the usefulness of PMMoV as a potential surrogate for human enteric viruses to assess virus removal by CS-RSF.

Efficient multiplexed genome engineering with a polycistronic tRNA and CRISPR guide-RNA reveals an important role of detonator in reproduction of Drosophila melanogaster

Genome association studies in human and genetic studies in mouse implicated members of the transmembrane protein 132 (TMEM132) family in multiple conditions including panic disorder, hearing loss, limb and kidney malformation. However, the presence of five TMEM132 paralogs in mammalian genomes makes it extremely challenging to reveal the full requirement for these proteins in vivo. In contrast, there is only one TMEM132 homolog, detonator (dtn), in the genome of fruit fly Drosophila melanogaster, enabling straightforward research into its in vivo function. In the current study, we generate multiple loss-of-function dtn mutant fly strains through a polycistronic tRNA-gRNA approach, and show that most embryos lacking both maternal and paternal dtn fail to hatch into larvae, indicating an essential role of dtn in Drosophila reproduction.

Quantifying Muscle Mass by Adjusting for Body Mass Index Is the Best for Discriminating Low Strength and Function in Japanese Older Outpatients

OBJECTIVES

To investigate the association of three muscle mass adjustment methods with low muscle strength (MS) and low physical function (PF) defined by the Asian Working Group for Sarcopenia (AWGS) 2019 criteria.

DESIGN

Cross-sectional study.

SETTING

Clinical setting.

PARTICIPANTS

We included 361 outpatients (77.9 ± 5.9 years) without scheduled orthopedic surgery or activities of daily living disability.

MEASUREMENTS

Appendicular skeletal muscle mass (ASM) was measured by dual-energy X-ray absorptiometry, then divided by height-square (ht2), body weight, and body mass index (BMI) to calculate the ASM indexes. We assessed grip strength, gait speed, short physical performance battery, and five-time chair stand test. Low MS and low PF were defined by the AWGS2019 criteria. To compare the association of three muscle mass adjustments with low MS and low PF, multiple logistic regression analysis was performed, adjusted for age in each sex.

RESULTS

Participants with low MS was 31.5%, low PF was 50.1%. After adjustment, only ASM/BMI was significantly associated with all independent variables, such as low MS, low PF, and either of these, with the odds ratios of 2.09, 2.08, and 2.50 for males; and 1.87, 2.43, and 2.71 for females, respectively.

CONCLUSION

Our findings suggest that ASM/BMI is best associated with low MS and low PF in older Japanese outpatients. Longitudinal outcome studies are needed to confirm our findings.

Association between Sarcopenia and Fall Risk According to the Muscle Mass Adjustment Method in Japanese Older Outpatients

We investigated whether the association between sarcopenia and fall risk (FR) differs according to the muscle mass adjustment method in 357 outpatients who were not disabled in the activities of daily living or indicated for orthopedic surgery. Sarcopenia was diagnosed by the Asian Working Group for Sarcopenia (AWGS) 2019 criteria, using adjusting methods of muscle mass by height squared (ht2), body mass index (BMI), or any of these (i.e., ht2-adjusted Sarc", "BMI-adjusted Sarc", or "ht2 and/or BMI-adjusted Sarc, respectively). FR was defined by FR index ≥10. There were 111, 105, and 157 participants with ht2-adjusted, BMI-adjusted, and ht2 and/or BMI-adjusted Sarc, respectively. After multivariable adjustment, ht2 and/or BMI-adjusted Sarc was the most closely associated with FR [odds ratio and 95% confidence interval: 2.94, 1.75-4.93]. Our data suggest that the sarcopenia definition using low ASM/ht2 and/or ASM/BMI muscle mass might better predict adverse outcomes in older patients.

Changes in nutritional status by recovery phase interventions would be a powerful determinant of cardiovascular prognosis in heart failure patients

Background

Adequate nutrition has been proposed for better cardiovascular prognosis as well as fitness, although the impact of the “changes” in nutrition and fitness at recovery phase on the future prognosis has been unclear.

Purpose

We aimed to examine whether the change in nutritional level as a result of dietary intervention combined with exercise would determine patients' cardiovascular prognosis.

Methods

This study involved 398 consecutive patients who participated in phase II comprehensive cardiac rehabilitation (CCR) for at least three months. All patients underwent cardiopulmonary exercise test (CPX) at the initial and completion periods of CCR. Individual dietary guidance was periodically performed with exercise. Peak oxygen uptake (PVO2) was measured through CPX to evaluate the fitness level, whereas nutritional status was evaluated using the geriatric nutritional risk index (GNRI). Patients were divided in two groups according to the baseline GNRI and the change in GNRI (ΔGNRI) by the median, respectively, to compare their prognosis between groups. Then they were classified into four categories according to the median values of the changes in GNRI (ΔGNRI) and PVO2 (ΔPVO2) during CCR: “Both improved”, “Only GNRI improved”, “Only PVO2 improved” and “Both NOT improved”, to compare MACCE-free rate between categories.

Results

The rate of MACCE showed significant difference between categories (14%, 18%, 19% and 36%, p<0.001), which was approximately 2 times higher in “Both NOT improved” than the others. Kaplan-Meier analysis showed that according to the level of ΔGNRI, “higher ΔGNRI group” showed significantly higher in MACCE-free survival rate than “lower ΔGNRI group” (log rank p=0.010), whereas there was no significant difference according to the baseline GNRI (see figure). According to the categories divided by ΔGNRI and ΔPVO2, MACCE-free rate was significantly lower in “Both NOT improved” (log rank p<0.001) compared to the other categories. Cox proportional hazard regression analysis revealed that “both NOT improved” was an independent predictor of MACCE (hazard ratio, 2.1, 95% confident interval, 1.344–3.175, p<0.001).

Conclusion

Changes in nutritional level would determine patients' cardiovascular prognosis rather than the baseline nutritional level. Non-responders who showed no improvement in nutritional or fitness by interventions may result in a poor cardiovascular outcome.

Funding Acknowledgement

Type of funding source: None

Suitability of pepper mild mottle virus as a human enteric virus surrogate for assessing the efficacy of thermal or free-chlorine disinfection processes by using infectivity assays and enhanced viability PCR

Evaluating the efficacy of disinfection processes to inactivate human enteric viruses is important for the prevention and control of waterborne diseases caused by exposure to those viruses via drinking water. Here, we evaluated the inactivation of two representative human enteric viruses (adenovirus type 40 [AdV] and coxsackievirus B5 [CV]) by thermal or free-chlorine disinfection. In addition, we compared the infectivity reduction ratio of a plant virus (pepper mild mottle virus [PMMoV], a recently proposed novel surrogate for human enteric viruses for the assessment of virus removal by coagulation‒rapid sand filtration and membrane filtration) with that of the two human enteric viruses to assess the suitability of PMMoV as a human enteric virus surrogate for use in thermal and free-chlorine disinfection processes. Finally, we examined whether conventional or enhanced viability polymerase chain reaction (PCR) analysis using propidium monoazide (PMA) or improved PMA (PMAxx) with or without an enhancer could be used as alternatives to infectivity assays (i.e., plaque-forming unit method for AdV and CV; local lesion count assay for PMMoV) for evaluating virus inactivation by disinfection processes. We found that PMMoV was more resistant to heat treatment than AdV and CV, suggesting that PMMoV is a potential surrogate for these two enteric viruses with regard to thermal disinfection processes. However, PMMoV was much more resistant to chlorine treatment compared with AdV and CV (which is chlorine-resistant) (CT value for 4-log₁₀ inactivation: PMMoV, 84.5 mg-Cl₂·min/L; CV, 1.15-1.19 mg-Cl₂·min/L), suggesting that PMMoV is not useful as a surrogate for these enteric viruses with regard to free-chlorine disinfection processes. For thermal disinfection, the magnitude of the signal reduction observed with PMAxx-Enhancer-PCR was comparable with the magnitude of reduction in infectivity, indicating that PMAxx-Enhancer-PCR is a potential alternative to infectivity assay. However, for free-chlorine disinfection, the magnitude of the signal reduction observed with PMAxx-Enhancer-PCR was smaller than the magnitude of the reduction in infectivity, indicating that PMAxx-Enhancer-PCR underestimated the efficacy of virus inactivation (i.e., overestimated the infectious virus concentration) by chlorine treatment. Nevertheless, among the PCR approaches examined in the present study (PCR alone, PMA-PCR or PMAxx-PCR either with or without enhancer), PMAxx-Enhancer-PCR provided the most accurate assessment of the efficacy of virus inactivation by thermal or free chlorine disinfection processes.

UTX/KDM6A suppresses AP-1 and a gliogenesis program during neural differentiation of human pluripotent stem cells

BACKGROUND

UTX/KDM6A is known to interact and influence multiple different chromatin modifiers to promote an open chromatin environment to facilitate gene activation, but its molecular activities in developmental gene regulation remain unclear.

RESULTS

We report that in human neural stem cells, UTX binding correlates with both promotion and suppression of gene expression. These activities enable UTX to modulate neural stem cell self-renewal, promote neurogenesis, and suppress gliogenesis. In neural stem cells, UTX has a less influence over histone H3 lysine 27 and lysine 4 methylation but more predominantly affects histone H3 lysine 27 acetylation and chromatin accessibility. Furthermore, UTX suppresses components of AP-1 and, in turn, a gliogenesis program.

CONCLUSIONS

Our findings revealed that UTX coordinates dualistic gene regulation to govern neural stem cell properties and neurogenesis-gliogenesis switch.

Drosophila models of pathogenic copy-number variant genes show global and non-neuronal defects during development

While rare pathogenic copy-number variants (CNVs) are associated with both neuronal and non-neuronal phenotypes, functional studies evaluating these regions have focused on the molecular basis of neuronal defects. We report a systematic functional analysis of non-neuronal defects for homologs of 59 genes within ten pathogenic CNVs and 20 neurodevelopmental genes in Drosophila melanogaster. Using wing-specific knockdown of 136 RNA interference lines, we identified qualitative and quantitative phenotypes in 72/79 homologs, including 21 lines with severe wing defects and six lines with lethality. In fact, we found that 10/31 homologs of CNV genes also showed complete or partial lethality at larval or pupal stages with ubiquitous knockdown. Comparisons between eye and wing-specific knockdown of 37/45 homologs showed both neuronal and non-neuronal defects, but with no correlation in the severity of defects. We further observed disruptions in cell proliferation and apoptosis in larval wing discs for 23/27 homologs, and altered Wnt, Hedgehog and Notch signaling for 9/14 homologs, including AATF/Aatf, PPP4C/Pp4-19C, and KIF11/Klp61F. These findings were further supported by tissue-specific differences in expression patterns of human CNV genes, as well as connectivity of CNV genes to signaling pathway genes in brain, heart and kidney-specific networks. Our findings suggest that multiple genes within each CNV differentially affect both global and tissue-specific developmental processes within conserved pathways, and that their roles are not restricted to neuronal functions.

Rare copy-number variants (CNVs), or large deletions and duplications in the genome, are associated with both neuronal and non-neuronal clinical features. Previous functional studies for these disorders have primarily focused on understanding the cellular mechanisms for neurological and behavioral phenotypes. To understand how genes within these CNVs contribute to developmental defects in non-neuronal tissues, we assessed 79 homologs of CNV and known neurodevelopmental genes in Drosophila models. We found that most homologs showed developmental defects when knocked down in the adult fly wing, ranging from mild size changes to severe wrinkled wings or lethality. Although a majority of tested homologs showed defects when knocked down specifically in wings or eyes, we found no correlation in the severity of the observed defects in these two tissues. A subset of the homologs showed disruptions in cellular processes in the developing fly wing, including alterations in cell proliferation, apoptosis, and cellular signaling pathways. Furthermore, human CNV genes also showed differences in gene expression patterns and interactions with signaling pathway genes across multiple human tissues. Our findings suggest that genes within CNV disorders affect global developmental processes in both neuronal and non-neuronal tissues.

Predictors of Cerebral Aneurysm Rupture after Coil Embolization: Single-Center Experience with Recanalized Aneurysms

BACKGROUND AND PURPOSE

Recanalization after coil embolization is widely studied. However, there are limited data on how recanalized aneurysms rupture. Herein, we describe our experience with the rupture of recanalized aneurysms and discuss the type of recanalized aneurysms at greatest rupture risk.

MATERIALS AND METHODS

A total of 426 unruptured aneurysms and 169 ruptured aneurysms underwent coil embolization in our institution between January 2009 and December 2017. Recanalization occurred in 38 (8.9%) of 426 unruptured aneurysms (unruptured group) and 37 (21.9%) of 169 ruptured aneurysms (ruptured group). The Modified Raymond-Roy classification on DSA was used to categorize the recanalization type. Follow-up DSA was scheduled until 6 months after treatment, and follow-up MRA was scheduled yearly. If recanalization was suspected on MRA, DSA was performed.

RESULTS

In the unruptured group, the median follow-up term was 74.0 months. Retreatment for recanalization was performed in 18 aneurysms. Four of 20 untreated recanalized aneurysms (0.94% of total coiled aneurysms) ruptured. In untreated recanalized aneurysms, class IIIb aneurysms ruptured significantly more frequently than class II and IIIa (P = .025). In the ruptured group, the median follow-up term was 28.0 months. Retreatment for recanalization was performed in 16 aneurysms. Four of 21 untreated recanalized aneurysms (2.37% of total coiled aneurysms) ruptured. Class IIIb aneurysms ruptured significantly more frequently than class II and IIIa (P = .02).

CONCLUSIONS

The types of recanalization after coil embolization may be predictors of rupture. Coiled aneurysms with class IIIb recanalization should undergo early retreatment because of an increased rupture risk.

Association of Muscle Strength and Gait Speed with Cross-Sectional Muscle Area Determined by Mid-Thigh Computed Tomography - A Comparison with Skeletal Muscle Mass Measured by Dual-Energy X-Ray Absorptiometry

BACKGROUND

Muscle mass is often mentioned not to reflect muscle strength. For muscle mass assessment skeletal muscle index (SMI) is often used. We have reported that dual-energy X-ray absorptiometry (DXA)-derived SMI does not change with age in women, whereas the cross-sectional muscle area (CSMA) derived from computed tomography (CT) does.

OBJECTIVES

The present study aimed to compare CT and DXA for the assessment of muscle tissue.

DESIGN AND SETTING

Cross-sectional study in the local residents.

PARTICIPANTS

A total of 1818 subjects (age 40-89 years) randomly selected from community dwellers underwent CT examination of the right mid-thigh to measure the cross-sectional muscle area (CSMA). Skeletal muscle mass (SMM) was measured by DXA. The subjects performed physical function tests such as grip strength, knee extension strength, leg extension strength, and gait speed. The correlation between CT-derived CSMA and DXA-derived SMM along with their association with physical function was examined.

RESULTS

After controlling for related factors, the partial correlation coefficient of muscle cross-sectional area (CSA) with physical function was larger than that of DXA-derived SMM for gait speed in men (p=0.002) and knee extension strength in women (p=0.03). The partial correlation coefficient of quadriceps (Qc) CSA with physical function was larger than that of DXA-derived SMM for leg extension power in both sexes (p=0.01), gait speed in men (p<0.001), and knee extension strength in women (p<0.001).

CONCLUSION

Mid-thigh CT-derived CSMA, especially Qc CSA, showed significant associations with grip strength, knee extension strength, and leg extension power, which were equal to or stronger than those of DXA-derived SMM in community-dwelling middle-aged and older Japanese people. The mid-thigh CSMA may be a predictor of mobility disability, and is considered to be useful in the diagnosis of sarcopenia.

Dynamics of Uncrystallized Water, Ice, and Hydrated Polymer in Partially Crystallized Poly(vinylpyrrolidone)-Water Mixtures

In this study, we investigated the cooperative molecular dynamics of poly(vinylpyrrolidone) (PVP), ice, and uncrystallized water (UCW) in partially crystallized PVP-water mixtures by means of broadband dielectric spectroscopy. Three relaxation processes, denoted I, II, and III, were observed at temperatures ranging from immediately below the crystallization temperature (T_c) to approximately 200 K. At temperatures of 173-193 K, processes I and II cannot be distinguished. Below 168 K, process II separates into two processes: process IV at higher frequencies and process V at lower frequencies. Process I contributes to process V. In partially crystallized mixtures, process I originates from UCW in an uncrystallized phase with PVP. Process II is attributed to ice in the mixture, with a relaxation time that is 2 orders of magnitude smaller than that of pure ice. The concentration dependence of the strength of process II and the relaxation time relative to that of ice in bovine serum albumin (BSA)-water and gelatin-water mixtures strongly support this conclusion. Observation of processes IV and V indicates the presence of multiple ice relaxation processes. Process III is attributed to the α process of PVP in the uncrystallized phase in 40 and 50 wt % PVP mixtures. For mixtures with 30 wt % PVP or less, process III is attributed not only to the α process of PVP but also to interfacial polarization.

The first case of chronic pulmonary Mycobacterium shigaense infection in an immunocompetent patient

Mycobacterium shigaense has recently been recognized as an emerging human pathogen, and is well known as a skin pathogen in immunocompromised individuals. In this report we describe the first case of chronic pulmonary infectious disease caused by M. shigaense in an immunocompetent individual.

Yap1 promotes proliferation of transiently amplifying stress erythroid progenitors during erythroid regeneration

In contrast to steady-state erythropoiesis, which generates new erythrocytes at a constant rate, stress erythropoiesis rapidly produces a large bolus of new erythrocytes in response to anemic stress. In this study, we illustrate that Yes-associated protein (Yap1) promotes the rapid expansion of a transit-amplifying population of stress erythroid progenitors in vivo and in vitro. Yap1-mutated erythroid progenitors failed to proliferate in the spleen after transplantation into lethally irradiated recipient mice. Additionally, loss of Yap1 impaired the growth of actively proliferating erythroid progenitors in vitro. This role in proliferation is supported by gene expression profiles showing that transiently amplifying stress erythroid progenitors express high levels of genes associated with Yap1 activity and genes induced by Yap1. Furthermore, Yap1 promotes the proliferation of stress erythroid progenitors in part by regulating the expression of key glutamine-metabolizing enzymes. Thus, Yap1 acts as an erythroid regulator that coordinates the metabolic status with the proliferation of erythroid progenitors to promote stress erythropoiesis.

4332Benefit of sinus rhythm restoration in acute decompensated heart failure patients with atrial tachyarrhythmia treated with landiolol

Background

Atrial tachyarrhythmias (ATA), such as atrial fibrillation / atrial tachycardia are frequently observed in patients with acute decompensated heart failure (ADHF). Because ATA leads to clinical deterioration and worsen HF, the conversion and prevention of ATA is important of ADHF with ATA. Landiolol, an ultrashort-acting intravenous beta-1 blocker, was developed and has been used for the treatment of ATA.

Purpose

We evaluated the acute effect of landiolol treatment on heart rate or blood pressure (BP), also the rates and benefits of sinus rhythm (SR) restoration among AHF patients with ATA treated with landiolol.

Methods

We studied 67 consecutive HF patients with ATA (age: 67±12 years, 36 male) treated with landiolol from 2015 to December 2017 at our University Hospital. They were compared with 50 paired subjects, matched for gender, age and baseline BP who developed HF with ATA from HIJ-HF 2 study (consisted of HF patients hospitalized between 2013 and 2014).

Results

At the start of landiolol treatment, mean left ventricular ejection fraction (LVEF) was 41±14%. The median maintenance dose of landiolol was 3.0 (1.0–12.0) μ/kg/min and the median treatment duration of landiolol was 5 (1–24) days. After 6 hours from administration of landiolol, mean HR decreased significantly from 140±18 to 100±21 bpm (p<0.05), whereas BP was not difference during landiolol treatment. Sinus rhythm was restored spontaneously in 15 (22%), and by electrical or pharmacological cardioversion in 5 (7%) during a treatment with intravenous landiolol. Furthermore, sinus rhythm was restored in 22 patients using additional rhythm control treatment, such as amiodarone or catheter ablation after intravenous landiolol treatement. Eight patients experienced in-hospital death. Forty-one (69%) of 59 patients discharged alive were in SR. During the follow-up period of 16±12 months, 4 patients died and 12 patients experienced rehospitalization due to worsening HF after hospital discharge. There was a significant higher rate of death or HF rehospitalization in patients without SR restoration than patients with SR restoration (44% vs. 20%, p<0.05) (Figure A). Compared with 50 paired subjects from HIJ-HF 2 study, those who treated with landiolol developed a significant higher rate of SR restoration (68% vs. 20%, p<0.05) (Figure B).

Figure 1

Conclusion

This study demonstrated that landiolol treatment was effective for both rate control and conversion to sinus rhythm in ADHF patient with ATA. We should consider that the benefits of rhythm control in ADHF patients with ATA during and after landiolol treatment.

P2528Responsiveness to nutritional intervention would impact on future cardiovascular prognosis in poor fitness patients

Purpose

Nutritional improvement has been proposed for long-term cardiovascular prognosis as well as fitness recovery. We aimed to examine whether “responsiveness” to nutritional and exercise interventions would impact patients' cardiovascular prognosis even patients in low baseline fitness level.

Methods

We included 254 consecutive patients who participated in the phase II comprehensive cardiovascular rehabilitation (CCR) for at least three months. All patients underwent cardiopulmonary exercise test (CPX) at the initial and completion phases of CCR. Nutritional guidance was periodically performed individually during CCR. Peak oxygen uptake (PVO2) was measured through CPX to evaluate the fitness level, whereas nutritional status was evaluated using the geriatric nutritional risk index (GNRI). Patients were divided into “low fitness” and “normal fitness” groups based on the median of baseline PVO2. Each group was further classified into four categories according to the changes in VO2 and GNRI during CCR: “Both NOT improved”, “Only GNRI improved”, “Only PVO2 improved”, and “Both improved”.

Results

Cox proportional regression analysis showed that the category of “both NOT improved” was an independent predictor for cardiovascular risk among the baseline low fitness group (Hazard ratio: 4.5, p=0.007); whereas no significant difference among the normal fitness group. Kaplan-Meier analysis revealed that the event-free survival rate was significantly lower in the “both NOT improved” category (log rank p=0.002) among the baseline low fitness group (figure); whereas no significant difference among the normal fitness group.

GNRI/PVO2 improvement vs. prognosis

Conclusion

Responsiveness to nutritional and exercise intervention could be a predictive factor of cardiovascular prognosis even in low fitness patients.

Bimolecular Fluorescence Complementation (BiFC) in Tissue Culture and in Developing Tissues of Drosophila to Study Protein-Protein Interactions

Protein-protein interactions provide a common mechanism for regulating protein functions and also serve as the fundamental step of many biochemical reactions. To accurately determine the involvement and function of protein-protein interactions, it is crucial to detect the interactions with the minimum number of artifacts. In this chapter, we report the method of bimolecular fluorescence complementation (BiFC) in tissue culture and developing tissues of Drosophila, which allows the visualization of subcellular localization of protein-protein interactions in living cells.

Dual Role of a C-Terminally Truncated Isoform of Large Tumor Suppressor Kinase 1 in the Regulation of Hippo Signaling and Tissue Growth

The considerable amount of experimental evidence has defined the Hippo pathway as a tumor suppressive pathway and increased expression and/or activity of its oncogenic effectors is frequently observed in cancer. However, clinical studies have failed to attribute cancer development and progression to mutations in the pathway. In explaining this conundrum, we investigated the expression and functions of a C-terminally truncated isoform of large tumor suppressor kinase 1 (LATS1) called short LATS1 (sLATS1) in human cell lines and Drosophila. Intriguingly, through overexpression of sLATS1, we demonstrated that sLATS1 either activates or suppresses the activity of Yes-associated protein (YAP), one of the effectors of the Hippo pathway, in a cell type-specific manner. The activation is mediated through inhibition of full-length LATS1, whereas suppression of YAP is accomplished through sLATS1-YAP interaction. In HEK293T cells, the former mechanism may affect the cellular response more dominantly, whereas in U2OS cells and developing tissues in Drosophila, the latter mechanism may be solely carried out. Finally, to find the clinical relevance of this molecule, we examined the expression of sLATS1 in breast cancer patients. The transcriptome analysis showed that the ratio of sLATS1 to LATS1 was increased in tumor tissues comparing to their adjacent normal tissues.

Probing ultrafast spin-relaxation and precession dynamics in a cuprate Mott insulator with seven-femtosecond optical pulses

A charge excitation in a two-dimensional Mott insulator is strongly coupled with the surrounding spins, which is observed as magnetic-polaron formations of doped carriers and a magnon sideband in the Mott-gap transition spectrum. However, the dynamics related to the spin sector are difficult to measure. Here, we show that pump-probe reflection spectroscopy with seven-femtosecond laser pulses can detect the optically induced spin dynamics in Nd2CuO4, a typical cuprate Mott insulator. The bleaching signal at the Mott-gap transition is enhanced at ~18 fs. This time constant is attributable to the spin-relaxation time during magnetic-polaron formation, which is characterized by the exchange interaction. More importantly, ultrafast coherent oscillations appear in the time evolution of the reflectivity changes, and their frequencies (1400-2700 cm-1) are equal to the probe energy measured from the Mott-gap transition peak. These oscillations can be interpreted as the interference between charge excitations with two magnons originating from charge-spin coupling.

Evaluation of the suitability of a plant virus, pepper mild mottle virus, as a surrogate of human enteric viruses for assessment of the efficacy of coagulation-rapid sand filtration to remove those viruses

Here, we evaluated the removal of three representative human enteric viruses - adenovirus (AdV) type 40, coxsackievirus (CV) B5, and hepatitis A virus (HAV) IB - and one surrogate of human caliciviruses - murine norovirus (MNV) type 1 - by coagulation-rapid sand filtration, using water samples from eight water sources for drinking water treatment plants in Japan. The removal ratios of a plant virus (pepper mild mottle virus; PMMoV) and two bacteriophages (MS2 and φX174) were compared with the removal ratios of human enteric viruses to assess the suitability of PMMoV, MS2, and φX174 as surrogates for human enteric viruses. The removal ratios of AdV, CV, HAV, and MNV, evaluated via the real-time polymerase chain reaction (PCR) method, were 0.8-2.5-log₁₀ when commercially available polyaluminum chloride (PACl, basicity 1.5) and virgin silica sand were used as the coagulant and filter medium, respectively. The type of coagulant affected the virus removal efficiency, but the age of silica sand used in the rapid sand filtration did not. Coagulation-rapid sand filtration with non-sulfated, high-basicity PACls (basicity 2.1 or 2.5) removed viruses more efficiently than the other aluminum-based coagulants. The removal ratios of MS2 were sometimes higher than those of the three human enteric viruses and MNV, whereas the removal ratios of φX174 tended to be smaller than those of the three human enteric viruses and MNV. In contrast, the removal ratios of PMMoV were similar to and strongly correlated with those of the three human enteric viruses and MNV. Thus, PMMoV appears to be a suitable surrogate for human enteric viruses for the assessment of the efficacy of coagulation-rapid sand filtration to remove viruses.

Assessment of the efficacy of membrane filtration processes to remove human enteric viruses and the suitability of bacteriophages and a plant virus as surrogates for those viruses

Here, we evaluated the efficacy of direct microfiltration (MF) and ultrafiltration (UF) to remove three representative human enteric viruses (i.e., adenovirus [AdV] type 40, coxsackievirus [CV] B5, and hepatitis A virus [HAV] IB), and one surrogate of human caliciviruses (i.e., murine norovirus [MNV] type 1). Eight different MF membranes and three different UF membranes were used. We also examined the ability of coagulation pretreatment with high-basicity polyaluminum chloride (PACl) to enhance virus removal by MF. The removal ratios of two bacteriophages (MS2 and φX174) and a plant virus (pepper mild mottle virus; PMMoV) were compared with the removal ratios of the human enteric viruses to assess the suitability of these viruses to be used as surrogates for human enteric viruses. The virus removal ratios obtained with direct MF with membranes with nominal pore sizes of 0.1-0.22 μm differed, depending on the membrane used; adsorptive interactions, particularly hydrophobic interactions between virus particles and the membrane surface, were dominant factors for virus removal. In contrast, direct UF with membranes with nominal molecular weight cutoffs of 1-100 kDa effectively removed viruses through size exclusion, and >4-log₁₀ removal was achieved when a membrane with a nominal molecular weight cutoff of 1 kDa was used. At pH 7 and 8, in-line coagulation-MF with nonsulfated high-basicity PACls containing Al₃₀ species had generally a better virus removal (i.e., >4-log₁₀ virus removal) than the other aluminum-based coagulants, except for φX174. For all of the filtration processes, the removal ratios of AdV, CV, HAV, and MNV were comparable and strongly correlated with each other. The removal ratios of MS2 and PMMoV were comparable or smaller than those of the three human enteric viruses and MNV, and were strongly correlated with those of the three human enteric viruses and MNV. The removal ratios obtained with coagulation-MF for φX174 were markedly smaller than those obtained for the three human enteric viruses and MNV. However, because MS2 was inactivated after contact with PACl during coagulation pretreatment, unlike AdV, CV, MNV, and PMMoV, the removal ratios of infectious MS2 were probably an overestimation of the ability of coagulation-MF to remove infectious AdV, CV, and caliciviruses. Thus, PMMoV appears to be a suitable surrogate for human enteric viruses, whereas MS2 and φX174 do not, for the assessment of the efficacy of membrane filtration processes to remove viruses.

Elimination of representative contaminant candidate list viruses, coxsackievirus, echovirus, hepatitis A virus, and norovirus, from water by coagulation processes

We examined the removal of representative contaminant candidate list (CCL) viruses (coxsackievirus [CV] B5, echovirus type [EV] 11, and hepatitis A virus [HAV] IB), recombinant norovirus virus-like particles (rNV-VLPs), and murine norovirus (MNV) type 1 by coagulation. Water samples were subjected to coagulation with polyaluminum chloride (PACl, basicity 1.5) followed by either settling or settling and filtration. Together with our previously published results, the removal ratio order, as evaluated by a plaque-forming-unit method or an enzyme-linked immunosorbent assay after settling, was HAV>EV=rNV-VLPs≥CV=poliovirus type 1=MNV>adenovirus type 40 (range, 0.1-2.7-log₁₀). Infectious HAV was likely inactivated by the PACl and therefore was removed to a greater extent than the other viruses. A nonsulfated high-basicity PACl (basicity 2.1), removed the CCL viruses more efficiently than did two other sulfated PACls (basicity 1.5 or 2.1), alum, or ferric chloride. We also examined the removal ratio of two bacteriophages. The removal ratios for MS2 tended to be larger than those of the CCL viruses, whereas those for φX174 were comparable with or smaller than those of the CCL viruses. Therefore, φX174 may be a useful conservative surrogate for CCL viruses during coagulation.

Radiofrequency ablation of pulmonary tumors near the diaphragm

PURPOSE

To retrospectively evaluate the feasibility, safety, and efficacy of radiofrequency ablation (RFA) of lung tumors located near the diaphragm.

MATERIALS AND METHODS

A total of 26 patients (15 men, 11 women; mean age, 61.5 years±13.0 [SD]) with a total of 29 lung tumors near the diaphragm (i.e., distance<10mm) were included. Mean tumor diameter was 11.0mm±5.3 (SD) (range, 2-23mm). Efficacy of RFA, number of adverse events and number of adverse events with a grade≥3, based on the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0, were compared between patients with lung tumors near the diaphragm and a control group of patients with more distally located lung tumors (i.e., distance≥10mm).

RESULTS

RFA was technically feasible for all tumors near the diaphragm. Four grade 3 adverse events (1 pneumothorax requiring pleurodesis and 3 phrenic nerve injuries) were observed. No grade≥4 adverse events were reported. The median follow-up period for tumors near the diaphragm was 18.3 months. Local progression was observed 3.3 months after RFA in 1 tumor. The technique efficacy rates were 96.2% at 1 year and 96.2% at 2 years and were not different, from those observed in control subjects (186 tumors; P=0.839). Shoulder pain (P<0.001) and grade 1 pleural effusion (P<0.001) were more frequently observed in patients with lung tumor near the diaphragm. The rates of grade≥3 adverse events did not significantly differ between tumors near the diaphragm (4/26 sessions) and the controls (7/133 sessions) (P=0.083).

CONCLUSION

RFA is a feasible and effective therapeutic option for lung tumors located near the diaphragm. However, it conveys a higher rate of shoulder pain and asymptomatic pleural effusion by comparison with more distant lung tumors.